Stephen Leahy, International Environmental Journalist

Discovering Global Environmental Interconnections

Posts Tagged ‘GHG

The Most Important Number in Human History

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Carbon overload Carbon in atmosphere and amount in fossil fuel reserves

Carbon overload Carbon in atmosphere and amount in fossil fuel reserves

That number was 52 billion tonnes of CO2 in 2012

Only when this number declines will we know we’re making the shift to climate protection

By Stephen Leahy

UXBRIDGE, Canada, Dec 17 2012 (IPS) 

The most important number in history is now the annual measure of carbon emissions. That number reveals humanity’s steady billion-tonne by billion-tonne march to the edge of the carbon cliff, beyond which scientists warn lies a fateful fall to catastrophic climate change.

With the global total of climate-disrupting emissions likely to come in at around 52 gigatonnes (billion metric tonnes) this year, we’re already at the edge, according to new research.

To have a good chance of staying below two degrees C of warming, global emissions should be between 41 and 47 gigatonnes (Gt) by 2020, said Joeri Rogelj, a climate scientist at Switzerland’s Institute for Atmospheric and Climate Science in Zurich.

Only when we see the annual global emissions total decline will we know we’re making the shift to climate protection,” Rogelj told IPS.

Making the shift to a future climate with less than two degrees C of warming is doable and not that expensive if total emissions peak in the next few years and fall into the 41-47 Gt “sweet spot” by 2020, Rogelj and colleagues show in their detailed analysis published Sunday in the journal Nature Climate Change.

The study is the first to comprehensively quantify the costs and risks of emissions surpassing critical thresholds by 2020. Read the rest of this entry »

Killer Heat Waves and Floods Linked to Climate Change

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More than 5 million affected by flooding in Pakistan Sept 2011 - a repeat of 2010.

More than 5 million affected by flooding in Pakistan Sept 2011 – a repeat of 2010.

“The first law of humanity is not to kill your children.”

By Stephen Leahy

UXBRIDGE, Canada, Feb 27 2013 (IPS)

Killer heat waves, floods and storms are increasingly caused by climate change, new research reveals.

Scientists in Germany say they have found how greenhouse gases from burning fossil fuels are helping to trap the jet stream, resulting in extraordinary weather such as the 2010 Pakistan flood and the 2011 heat wave in the United States.

Human-driven climate change repeatedly disturbs the flow of atmospheric waves around the globe’s Northern hemisphere, said lead author Vladimir Petoukhov of the Potsdam Institute for Climate Impact Research (PIK) in Germany.rossby.waves1_

Giant atmospheric waves called Rossby waves are meanders in the strong, high-altitude winds known as jet streams and have a major influence on weather. These wave movements are caused by the difference in temperatures between the cold air from the Arctic and hot air from the tropics.

When the waves shift north, they suck warm air from the tropics to Europe, Russia, or the U.S., and when they swing down, they do the same thing with cold air from the Arctic, said Petoukhov.

“During several recent extreme weather events, these planetary waves almost freeze in their tracks for weeks,” he said. “So instead of bringing in cool air after having brought warm air in before, the heat just stays.”

This unnatural pattern is due to human heating of the climate through emissions of greenhouse gases that result from burning fossil fuels, according to the study published this week in Proceedings of the National Academy of Sciences.

However, this heating of the atmosphere is wildly uneven. The Arctic is warming two to three times faster than the global temperature rise of 0.8C and that affects the Rossby waves and is slowing the jet stream.

“(Our research) complements previous research that already linked such phenomena to climate change,” said Hans Joachim Schellnhuber, a co-author of the study. Read the rest of this entry »

Indigenous Peoples Needed to Meet the Challenge of Climate Change

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Gimuy Wallabarra Yidinji Dancers performing Welcome to the Country in Cairns, Australia .Photo: Gleb Raygorodetsky

By Stephen Leahy

First published at National Geographic NewsWatch

“Planning is not part of our culture. You just get up in the morning and do what you need to do for the day,” said Marilyn Wallace of the Kuku Nyungka ‘mob’ (aboriginal nation) in northern Queensland, Australia.

“Bama” or caring for their local territory is an important part of aboriginal culture and identity Wallace told participants at a mini-workshop in Cairns, Australia today Sunday March 25th prior to the start of the main workshop Climate Change Mitigation with Local Communities and Indigenous peoples on Monday.

Caring for the land includes monitoring the impacts of climate change and using traditional knowledge to keep or sequester carbon she said.

Click here for full article plus a video visit with Marilyn in her home country.

G8 Failure to Launch on Potential Climate Catastrophe

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Analysis by Stephen Leahy

BERLIN, Jul 13 (IPS)

The G8’s failure to make meaningful commitments on climate last week pushes the world ever closer to global climate catastrophe, experts warn. Without commitments to take action, there is little comfort in G8 countries’ agreement to keep overall global warming below 2.0 degrees Celsius.

“If they took the 2.0-degree commitment seriously, it would imply a vigourous and immediate carbon emission reduction programme, said Michael Oppenheimer, a professor of Geosciences and International Affairs at Princeton University in the U.S.

“It would mean carbon emissions would have to peak by 2020 and decline. That’s a tall order but that’s what needs to happen to stabilise at around 2.0 degrees C,” Oppenheimer told IPS.

The Group of Eight of the world’s largest economies comprises Britain, France, Germany, Italy, Russia, Canada, Japan and the United States.

Climate experts stress that 2.0 degrees is not in any way a guarantee of safety. There are already significant impacts currently from climate change. However, from what scientists know today, risks increase markedly over 2.0 degrees of warming, Oppenheimer warned.

Global temperatures have already risen 0.8 C in the last hundred years and will reach 1.2 to 1.5 C based on emissions already in the atmosphere.

“The climate system is unpredictable. Two degrees is just a guideline,” Oppenheimer said. Read the rest of this entry »

Written by Stephen

18/10/2009 at 5:36 pm

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